docs: HOWTO for cloud devops + update TEST_STAND manifests for new API Gateway

- HOWTO_IMPLEMENT_NEW_CLOUD_SERVICE.md: rules for implementing new managed services
  (naming, params, map-fixed blocks, operations, subresources, validation, checklist)
- HOWTO_ADD_NEW_SERVICE.md: how to add service to terraform provider pipeline
- TEST_STAND/*/main.tf: version 5.0.57, api_endpoint -> lk-api-gateway-test
- TEST_STAND/POSTGRES/resources.tf: rewritten for new map-fixed param structure

TEST_STAND/POSTGRES/resources.tf

@@ -1,38 +1,46 @@
 resource "nubes_postgres" "npg" {
-  resource_name      = "pg4tf033"
-  s3_uid             = var.s3_uid
-  resource_realm     = var.realm
-  resource_instances = 1
-  resource_memory    = 512
-  resource_c_p_u     = 500
-  resource_disk      = "1"
-  app_version        = "17"
-  json_parameters = jsonencode({
-    log_connections    = "off"
-    log_disconnections = "off"
-  })
-  enable_pg_pooler_master      = false
-  enable_pg_pooler_slave       = false
-  allow_no_s_s_l               = false
-  auto_scale                   = false
-  auto_scale_percentage        = 10
-  auto_scale_tech_window       = 0
-  auto_scale_quota_gb          = "1"
-  need_external_address_master = false
+  resource_name = "pg4tf033"
+
+  cluster_configuration = jsonencode({
+    platform  = var.realm
+    instances = 1
+    memory    = 512
+    cpu       = 500
+    disk      = "1"
+  })
+
+  startup_configuration = jsonencode({
+    appVersion = "17"
+  })
+
+  access_configuration = jsonencode({
+    needExternalAddressMaster = false
+  })
+
+  postgres_configuration = jsonencode({
+    enablePgPoolerMaster = false
+    enablePgPoolerSlave  = false
+    allowNoSsl           = false
+    s3Uid                = var.s3_uid
+    jsonParameters = jsonencode({
+      log_connections    = "off"
+      log_disconnections = "off"
+    })
+  })
+
+  backup_configuration = jsonencode({})
+
+  autoscale_configuration = jsonencode({
+    autoScale  = false
+    percentage = 10
+    techWindow = 0
+    quotaGb    = "1"
+  })
 
-  # suspend_on_destroy = false
   operation_timeout        = "11m"
   adopt_existing_on_create = true
 }
 
-
-# resource "nubes_s3bucket" "baba_bucket" {
-#   resource_name = "baba-buck-test1"
-#   s3_user_uid = var.s3_uid
-#   bucket_name   = "baba000"
-#   adopt_existing_on_create=true
-# }
-
 resource "nubes_postgres_user" "pg_user" {
   postgres_id              = nubes_postgres.npg.id
   username                 = "user0"
@@ -45,6 +53,5 @@ resource "nubes_postgres_database" "db2_app" {
   db_name                  = "db_terra"
   db_owner                 = nubes_postgres_user.pg_user.username
   adopt_existing_on_create = true
-  # suspend_on_destroy = false
 }